Internal combustion engine apparatus



April 18, 1939. H. w LTI INTERNAL COMBUSTION ENGINE APPARATUS Filed Sept. 22, 1936 Patented Apr. 18, 1939 UNITED STATES INTRNAL COMBUSTION ENGINE APPARATUS Heinrich Wlti, Winterthur, Switzerland, assignor to Sulzer Freres, Societe Anonyme, Winterthur, Switzerland Application September` 22,

1936, serial No,

101,894. In Switzerland October 1, 1935 3 Claims.

'Ihis invention relates to internal combustion engines and particularly to auxiliary apparatus for the production of scavenging-air therefor.

'I'he auxiliary apparatus of the invention comt prises one or more power pistons each of which is connected in tandem to and drives an air compressor piston for supplying scavenging-air to the engines. The power and compressor pistons are mounted on the same piston rod, in spaced I relation, with the compressor piston between the power piston and a crankshaft which is common to both. The power and compressor pistons are reciprocable in their respective cylinders which are separated from each other a suitable distance.

used which also serves to permit inspection of the power piston during substantially its entire stroke, and to prevent'air pollution, as will later be described.

It is an object of the invention to provide a combination of the foregoing described scavenging-air apparatus with an internal combustion engine, particularly of the two-cycle type such as arevused for power plants. The invention also 25 contemplates the provision of Imeans for circulating a cooling medium through the piston rod and in contact with the power piston.

The invention will be better understood from a consideration of the following description taken in conjunction with the accompanying drawing,

in which Fig. 1 is a schematic illustration of apparatus in accordance with the invention;

Fig. 2 is an elevation, with certain parts shown in section, of the scavenging-air apparatus of ghe invention taken along the line 2-2 of Fig.

; and

Fig. 3 is an elevation, with certain parts shown in section, taken along the line 3-3 of Fig. 2.

Fig. 1 illustrates a combination of apparatus in accordance with the invention comprising two ten-cylinder two-cycle internal combustion engines I, having scavenging-air manifolds 2 and 3, an exhaust conduit l, and auxiliary apparatus 45 5 for the production of scavenging-air for the said engines which includes a scavenging-air receiver 6 connected to the manifolds 2 and 3, and an exhaust conduit 'I which is connected to the exhaust conduit I of the engines.

The auxiliary machine 5, for compressing scavenging-air (illustrated in detail in Figs. 2 andv 3) consists of two cylinder-units each of which yis similar and the following description in the singular is understood to refer to each unit. Each unit has a power piston 3 reciprocable For this purpose a spacing member-is within a combustion or power cylinder 9. The power piston is mounted on a piston rod I II on which a compressor piston II is mounted in tandem therewith and reciprocable in a compression cylinder I2. The power and compression cylin- 5 ders are preferably arranged in upright positions and are spaced apart by means of the spacing member or lantern I3, having an opening I4 therein which not only permits inspection o f the power piston over the greater part of its length 10 but also prevents pollution of the scavenging and charging air by exhaust gases or partially carbonized oil from the combustion cylinder 9. The common piston rod II) engages the crosshead I5 of the connecting rod I6 which is mounted upon the crankshaft II.

A tubular slide-valve I8, mounted adjacent one side of the compression cylinder I2, is driven from the crankshaft I'I by the eccentric connecting rod I9, the double lever and guide rod 2|. The piston compressor I I is doubleacting and provided with Valve-controlled openings 22 and 23each of which serves as both an inlet and an outlet opening for the compression cylinder. An Inlet conduit 24 supplies air from the outside to the circumferential opening or passage 25 around the central portion of the slide valve I8. The opening 22 connects directly with the receiver 6 and the opening 23 connects through the central opening 23a in the valve I8, with the receiver 6.

The power piston 8 is constructed and arranged to receive its scavenging-air from the receiver 6 by means of a conduit 26 which is in communication with the ducts 21 Which are controlled by the check-valves 28. The ports 2'I lead directly into the cylinder 9 through suitable scavenging and charging ports. The head 3| of the power cylinder is provided with a. fuel Valve 32 of known construction which is supplied with fuel oil under pressure from any suitable source (not shown). l

The bottom 33 of the lantern I3 issloped to one side and at the low point is connected with a pipe 34 into which oil, wiped off the piston rod III, may be drained. 45

`The under portion of each power piston is cooled by means of a circulated uid coolingmedium. For this purpose, the -piston rod III has a central bore 35 and a concentric inner tube 36. 'Ihe tube 36 connects with an inlet opening 31 in the crosshead I5 which connects with a tubular telescopic member 38 connected to a con-- duit 39 leading .to a suitable source of cooling 'medium such as oil under pressure (not shown).

The conduit 35 connects with the outlet opening connected to a second tubular telescopic member 4I which connects to a conduit l2 leading to the source of cooling medium or to waste.

The power capacity of each power rcylinder is not appreciably more than necessary to operate the compressor piston. As the combustion power piston cylinder 8 is single-acting, but works in two-cycle, and the auxiliary machine 5 has two cylinder units, the cranks of which are displaced by 180 with respect to each other, the arrangement is balanced with respect to the distribution of output. In the case of a single cylinder unit a flywheel would have to be provided in order to be able to deliver the compression work in the double-acting compressor and in the combustion power cylinder at the compression stroke of the com'bustion power piston. Multi-cylinder scavenging-air producers have the advantage of a good balancing of masses as has already become known in connection with combustion engines.

The apparatus functions as follows: Air is passed from the receiver Ii through the conduit 26, the check-valves 28, the ducts 2l and through charging and scavenging ports (not shown) into the cylinder 9. As the power piston moves upwardly, the air is compressed-whereupon oil is injected into the cylinder 9 by means of the valve 32. The oil is ignited and the piston begins to move downwardly moving the compressor piston in the same direction. As the compressor piston begins to move downwardly, the slide valve I8 is in the position shown in Fig. 2, and the slide Valve moves upwardly clearing the opening 22 so that air is sucked into the compression cylinder through conduit 24 and passage 25. At the same time valve I8 clears opening 22 permitting the air to be forced out of the compression cylinder through the opening 23a and into the receiver 6. Valve I8 continues to move upwardlyand into the cylindrical bore 22a. thereby closing the passageway between opening 22 and the receiver 6. As the piston II reaches the lower end of its stroke and starts upwardly, the valve I8 clears the opening 23, permitting air to be sucked into the cylinder I2, and continues to move downwardly into the bore 24a closing the passageway between opening 23 and the receiver 6. Meanwhile the the telescopic member 33, the passageway 31 in the crosshead I5 and then upwardly through the tube 36 and in contact with the piston. The iluid then enters the bore 35 where it connects with the piston and ows through the outlet opening 40, into the telescopic member 4I, and into the.

conduit 42 from which it is either discharged to waste or returned to theV source of cooling medium.

In the foregoing description of operation, reference has been made to only one unit, it being understood that each unit in the system would operate similarly.

The auxiliary machine for producing the scavenging-air can also be formed as a floating-piston engine, since the power and compressor pistons work as floating pistons without a crank drive.

I claim: 1. In combination, an internal combustionengine plant including at least one principal combustion engine of the type requiringy scavenging or charging air, and a separate auxiliary air compressor unit supplying said air for said principal combustion engine, said auxiliary unit comprising at least one engine-driven compressor including an engine cylinder, an engine piston, a piston rod, a connecting rod, a crank, an air pump cylinder arranged between said engine cylinder and said crank, and an air pump piston arranged in said pump cylinder on said piston rod between said engine piston and said connecting rod, a spider securing said engine cylinder to said pump cylinder in such manner that said engine piston is exposed between said cylinders, whereby to allow inspection of said engine piston during operation and to prevent pollution of said air, and an air conduit directly connecting said principal com-- bustion engine and said air compressor unit to convey said scavenging or charging air.

2. An internal combustion engineplant accord- Y ing to claim 1 wherein said principal engine comprises a plurality of rows of power cylinders the scavenging air for .which is supplied by an auxiliary'air-compressor unit comprising only a few cylinders compared with the number of cylinders in said principal engine.

3. In combination with an internal combustion engine, auxiliary apparatus for the production of scavenging-air therefor, which comprises a power piston, a compressor piston, a crank, a piston rod on which both pistons are mounted in tandem with'said compressor piston between said power piston and said crank, cylinders for said pistons, a spider for supporting the cylinders in spaced relation whereby to allow inspection of said engine piston during operation and to prevent pollution of said air, and an air conduit directly connecting said auxiliary apparatus and said combustion engine to convey said scavenging air.

HEINRICH WLTI. 

